Sorry, are you confirming that the Premier AF-40K water softener from Costco uses Demand-Initiated Regeneration? Meaning it will only regenerate when it is needed, not base on a set timer? If yes, I am getting it

Help me understand... you would want a higher grains rating so that the unit doesn't regenerate as often? as the process of regenerating will use a lot of water?

Also, I have done some reading and there are two types of control:

1. Timer base regeneration or;
2. Demand-initiated regeneration (DIR)

The DIR type is definitely going to save more water in the long run.

Anyone know if the Premier water softener sold by Costco is timer or demand-initiated base regeneration?

It's a mix.

I took a picture of the box a few months ago but I deleted it. My memory says the box listed it is as demand-initiated. From costco.ca, it says:

Digital demand regeneration valve with bypass valve preinstalled

Thing is, this water softener will regenerate after 15 days if there hasn't been a recharge/regeneration of soft water. So if you don't use enough soft water after 15 days since the last regeneration, this system will trigger one. You can't override this setting. It's in the installation manual that's linked in the Costco.ca page, but it's not on Watts' website. I'm not sure if that sears.ca one linked earlier has a similar setting or not.

From my shopping experience, there's a balance that you need to consider. Yes, the more grains means the water softener will regenerate less often. However, the plumbers I spoke with suggested I don't go too big of a system that would cause problems down the road if the softener didn't regenerate periodically (it's the idea that if things stagnate that whatever parts could clog etc.).

Been looking at this one and the Kenmore 24,000 grain. The Kenmore is probably too small for my needs (checked at sears and was told yesterday only 14 left in Western Canada). I just called my local Costco (Regina). They just got 10 of the 40,000 grain in this morning (so 11 in stock). The website item # does not match what's in store, but it is the same softener (40,000 grain made by Watt).

I saw these in the Barrie Costco last week. I would definitely buy one at this price, but it's a little small for my water conditions.

Make sure you guys size these properly, if you get one that is undersized, it will probably still work, but it will use WAY more salt.
Something like up to 5 times as much salt for the same amount of softened water. This site has some good info on how to properly size a softener. http://www.aquatell.ca/knowledge-center ... r-softener

A email from Watts Water, the maker of this Premier Water Softener from Costco, confirmed to me that the AF40K does indeed regenerate on demand and will force a regeneration after 14days without a regen.